Electrical contact means



Feb. 11, 1941. H, DQUGLAS 2,231,325

ELECTRI CAL CONTACT MEANS Original Filed Feb. 26, 1935 2 4/ it 48 44 3 g 42 40 v1 HARRY A. LET/(961 48 32 53 INVENTOR.

48 27 QRNEY Patented Feb. 11, 1941 UNITED STATES PATENT OFFICE ELECTRICAL CONTACT MEANS Harry A. Douglas, Bronson, Mich, assignor to Kingston Products Corporation, a corporation of Indiana Continuation 02 application Serial No. 8,315, Feb- My invention relates to electrical contact means, such as may be used in electric switches and the like, and more particularly to electrical contacts and terminals associated therewith, and

the principal object of my invention is to provide a new and improved electrical contact means of this type. In the drawing accompanying this specification, and forming part of this application, I have shown, for purposes of illustration, one form which my invention may assume.

This application is substituted for my formally abandoned application, flied February 26, 1935, Serial Number 8,315.

In the drawing:

Figure 1 is a vertical sectional view of one form of my invention, as it may be embodied in an electrical switch, with certain duplicate parts omitted,

Figure 2 is a fragmentary rear elevation of the base of the switch shown in Figure 1, with part of the electrical contacts assembled with the base,

Figure 3 is a section taken on the line 3-3 of Figure 1, looking in the direction of the arrows, and

Figure 4 is a perspective view of parts, disassembled, included ln 9. contact means, shown in Figure 1.

Referring to Figure 1 of the drawing, a panel M has mounted thereon a switch casing ll, of cup-shape, having a bottom i2 and a tubular portion i3 extending therefrom. Fastened to the bottom l2 in any suitable manner is a threaded nipple l4 extending through an aperture in the panel l0, and engaged by a nut IS. A shaft I6 is disposed through the nipple l4 and is provided at one end with an operating handle l1. At the other end the shaft I6 is provided with a laterally extending member i0 drlvingly connected in any suitable manner to an insulating carrier I9.

The insulating carrier I9 is here shown as provided with an electrical contact having a plurality of depressions, two of which, 2i, 22, are visible. The insulating carrier I3 is also provided with a plurality of depressions, one of which, 23, is visible.

Cooperable with the insulating carrier l9 and the contact 20 mounted thereon are a plurality of contact means, in this particular switch seven in number, three of which, 24, 26, 21, are visible in Figure 1, whereas two more, which would be otherwise visible in Figure 1, have been omitted for the sake of clearness. Inasmuch as all of the contact means, such as 24, 26, 21, are identical, only one of them will be described in detail.

The contact means 24 is here shown as of generally U-shape and desirably formed to that shape from flat stock, desirably of iron or steel. The U-shaped contact means 24 has legs 28, 29, reciprocably mounted in an insulating base 30. The base 30 is of suitable configuration to be received by the open end of the casing II and 10 may be fastened to the casing in any suitable manner (not shown). The inner face of the insulating base 30 is provided with a recess 3i, extending at right angles to a radius of the base, and having a circumferential width and a m radial width suflicient to slidably receive the leg 28 of the contact means 24. The recess 3| extends axially of the insulating base 30 to and merges with an aperture 32 in a boss 33 provided on the outer face of the insulating base 30. The aperture 32 has a cross-sectional shape similar to the cross-sectional shape of the leg 28. The bosses provided for the other contact means 24, 25, 26, 21 are identical with the boss 33 associated with the contact means 24, so that reference may be had to Figure 2 where one of the contact means has been removed from a boss 33 to more clearly show the apertures therein. The insulating base 30 is also provided on its inner face with a recess 34 extending at right angles to a radius of the base, the circumferential width of the recess 34 being suflicient to slidably receive the leg 29 of the contact means 24. The recess 34 is less in circumferential width than the recess 3i, the leg 29 being of less width than the leg 28. The recess 34 extends axially of the base 30 to, and merges with, an aperture 35 in the boss 33, which aperture may also be seen in Figure 2. The aperture 35 has a cross-sectional shape similar to that of the leg 29. The recesses 3i, 34 are joined by a recess 36 having arcuate walls 31, 38 which at one end merge with the circumferential ends of the recess 34 and at the other merge with the radially inner side of the recess 3i, at points spaced circumferentially from the circumferential ends of the recess 3|. The recess 38 extends axially to a point where the recesses IN, 34 merge with the apertures 32, 35 in the boss 33.

The bight of the U-shaped contact means 24 is provided with a contact 39, desirably of brass, which contact in this instance is provided by an originally separate piece analogous to a rivet, the head of which serves as the contact and the shank of which passes through an aperture in the bight of the U-shaped contact means 24 and is riveted or upset to fasten the contact; at the same time providing a projection 48. The projection 40 aids in holding in position one end of a helical spring 4|, disposed between the legs 28, 28, the other end of the spring 4| bearing against the bottom of the recess 38.

The leg 28 of the contact means 24 is longer than the leg 28, and extends through the insulating base 30 from the inner to the outer side thereof. At its outer end the leg 28 is provided with means for connecting an electrical conductor thereto comprising a screw 42 operable in a threaded hole through the leg 2!. Underneath the head of the screw 42 is provided a lock washer 44 having a central aperture, toward which project, from the annual portion of the washer, a plurality of spaced teeth, each twisted out of its own plane so as to form serrations 45 projecting laterally from both faces of the washer. The serrations 45 are adapted to lock the screw 42 and also hold a conductor 48, which may be placed between the washer 44 and the leg 28. In order to prevent turning of the washer 44 as the screws 42 turn, the washer is provided with a projection 46 extending transversely to a face of the washer and adapted to be received in an aperture 41 provided in the leg 28.

In assembling a contact means such as 24 with the base, let it be assumed that the screw 42 and washer 44 are not yet assembled with the leg 28. The spring 4| is positioned to have one end thereof disposed about the projection 40, and the legs 28, 28 are then inserted in the recesses ll, 84, the leg 28 passing through the aperture 32 in the boss 33. The washer 44 is then placed in the position shown in Figure 1 with the projection 46 through the aperture 41, and the screw 42 is placed through the aperture in the washer and threaded into the leg 28. It will be clear that the projection 46 prevents such movement of the contact means 24, toward the right, as viewed in Figure 1, as would permit the spring 4|, or the contact means as a whole, from becoming disassembled from the base 38. The same procedure is followed with all of the rest of the contact means, similar to the contact means 24, it may be desired to have mounted on the base 30. The base 30, with the contact means assembled therewith, may then be assembled with and fastened to the switch casing ll having the contact carrying member I! disposed therein. The springs 4! then bias the contacts into engagement with a contact, such as 20, carried by the insulating contact carrier I! or into engagement with the insulating contact carrier itself, depending upon the relation of the parts.

It will be evident that in the particular construction illustrated in Figure 1, since the contacts 39 of the contact means 24, 26 are in en-- gagement with the contact 20, an electrical connection will be formed between the contact means 24, 26, and, on the other hand, the contact 39 of the contact means 21, since it is in engagement with the insulating carrier i9 is not included in any completed circuit. However, the form and disposition of the contacts, such as 20, on the relatively movable element of the switch, and the number and arrangement of the contact means, such as 24, 25, 26, 21, is not material, as far as the present invention is concerned, and it will be obvious to those skilled in the art that any desired arrangement and relation may be adopted, which will permit of performance of the desired switching operations when the handie I! is turned.

Inviewoftheforegoingitwillbeobviousto those skilled in the art that my invention may be embodied in other constructions wherein the relatively movable elements may cooperate in waysotherthanthatdisclosed andmayassume a variety of forms, variously changed and modifled within the spirit of the invention.

In general it will be clear to those skilled in the art that the features of my invention need not all be used in one embodiment, and may be individually or collectively variously changed and modified, without departing from the spirit of the invention, or sacrificing all of the advantages thereof, and accordingly that the disclosure herein is illustrative only, and that my invention is not limited thereto.

What I claim and desire to secure by Letters Patent is:

1. Terminal means, comprising: a support, having an aperture; a body, slidably mounted in said aperture, and having portions extending from opposite surfaces of said support, one of said portions having means providing for the connection of a conductor, and having also an aperture; resilient means, engaging the other portion of said body, and constructed and arranged to urge said body in one direction with respect to said support; and means for preventmg unintentional disconnection of the conductor from said connection means, said preventing means having a part disposed through the aperture in said one portion, and constructed and arranged for engagement with a surface of said support to limit movement of said body in said one direction.

2. Terminal means, comprising: a support, having an aperture; a body, slidably mounted in said aperture, and having portions extending from opposite surfaces of said support; resilient means, eng ging one portion of said body, and constructed and arranged to urge said one portion in a direction away from said support; the other portion of said body having an aperture, and having also means for connecting a conductor to said body, said connecting means including washer means having a part disposed through the aperture in said other portion, and constructed and arranged to engage the adjacent surface of said support to limit movement of said body in said direction.

3. Terminal means, comprising: a support, having spaced apertures, and having a well communicating with said apertures; a body, having spaced legs arranged for sliding movement through respective apertures, at least one of said legs having portions extending from opposite surfaces of said support; resilient means, constructed and arranged to urge said body in one direction away from said support; one portion of said one leg having an aperture, and having also means for connecting a conductor to said body, said connecting means including washer means having a part disposed through the aperture in said one portion, and constructed and arranged to engage the adjacent surface of said support to limit movement of said body in said one direction.

4. Terminal means, comprising: a support, having spaced apertures of unequal width, and having also a well communicating with said apertures; a U-shaped body, having its legs arranged for sliding movement through respective apertures, each of said legs being of a width corresponding to the width of a respective aperture; the bight of said body being disposed adjacent one surface of said support, and one of said legs extending through its respective aperture and having a portion disposed adjacent the opposite surface of said support, said portion being provided with an aperture; resilient means interposed between said bight and the bottom of said well for urging said body in one direction; and means for connecting a conductor to said portion of said one leg, said means including washer means having a part disposed through the aperture in said portion and constructed and arranged to engage said opposite surface of said support to limit movement of said body in said one direction,

5. Terminal means, comprising: a support, having an aperture; a body, slidably mounted in said aperture, and having portions extending from opposite surfaces of said support, one of said portions having means providing for the connection of a conductor, and having also an aperture; the other portion of said body, being constructed and arranged to project with respect to said support to engage contact means; and means for preventing unintentional disconnection of the conductor from said connection means, said preventing means having a part disposed through the aperture in said one portion, and constructed and arranged for engagement with a surface of said support to limit movement of said body in said one direction.

6; Terminal means, comprising: a support, having an aperture including a slot; a body, slidably mounted in said aperture, and having portions extending from opposite surfaces of said support, one of said portions being slidable in said slot and having means including a screw providing for the connection of a conductor, and having'also an aperture; resilient means, engaging the other portion of said body, and constructed and arranged to urge said body in one direction with respect to said support; and means for preventing unintentional disconnection of the conductor from said connection means, said preventing means having a part disposed in the aperture in said oneportion, and constructed and arranged for engagement with a surface of said support to limit movement of said body in said one direction.

7. Terminal means, comprising: a support, having an aperture; a body, slidably mounted in said aperture, and having portions extending from opposite surfaces of said support; one portion of said body constructed and arranged to engage contact means; the other portion of said body having an aperture, and having also means for connecting a conductor to said body, said connecting means including washer means having a part disposed through the aperture in said other portion, and constructed and arranged to engage the adjacent surface of said support to limit movement of said body in said direction.

8. Terminal means, comprising: a support, having spaced apertures; a body, having spaced legs arranged for sliding movement through respective apertures, at least one of said legs having portions extending from opposite surfaces of said support; resilient means, constructed and arranged to urge said body in one direction away from said support; one portion of said one leg having an aperture, and having also means for connecting a conductor to said body, said connecting means including washer means having a part disposed in the aperture in said one portion, and constructed and arranged to engage the adjacent surface of said support to limit movement of said body in said one direction.

9. Terminal means, comprising: a support, having a well, and spaced apart apertures arranged tangentially to said well and communicating therewith; a body, having spaced legs arranged for sliding movement through respective apertures, at least one of said legs having portions extending from opposite surfaces of said support; resilient means, constructed and arranged to urge said body in one direction away from said support; one portion of said one leg having an aperture, and having also means for connecting a conductor to said body, said connecting means including washer means having a part disposed through the aperture in said one portion, and constructed and arranged to engage the adjacent surface of said support to limit movement of said body in said one direction.

10. Terminal means, comprising: a body having a pair of parallel portions joined together at one end by a bight portion extending at right angles to said parallel portions, one of said parallel portions and said bight portion being of the same width, a contact being provided on said bight portion, the other parallel portion being of a greater width and length than said one portion, and provided with means to which a conductor may be secured.-

HZARRY A. DOUGLAS. f 

